Red-ox drain cleaning composition

ABSTRACT

A drain cleaning composition is provided consisting essentially of 20 to 60 weight percent of an oxidizing agent, 1 to 30 weight percent of a reducing agent, and from about 20 to 75 weight percent of an alkali metal hydroxide, wherein the composition is capable of producing at least 230 calories of heat per gram upon dissolution in water.

BACKGROUND OF THE INVENTION

Compositions containing mixtures of reducing agents and oxidizing agentswhich are capable of producing heat upon interaction thereof (i.e.red-ox mixtures) have long been known in the art. Thus, for example,U.S. Pat. Nos. 3,722,752 to Kenkare et al and 3,772,203 to Gray disclosecosmetic compositions which contain red-ox mixtures for self-heatingpurposes. U.S. Pat. No. 3,862,866 to Timmerman et al discloses a gasgenerator composition utilizing a red-ox mixture.

Several patents additionally disclose drain cleaning compositionscontaining caustic alkali, a wetting or foaming agent and certainadditional ingredients which may include reducing agents or oxidizingagents. For example, U.S. Pat. No. 2,997,444 to Martin et al discloses adrain cleaning composition containing sodium hydroxide and ananti-clogging agent such as sodium sulfide or sodium thioglycolate aswell as a surface active wetting agent. U.S. Pat. No. 3,697,431 toSummerfelt discloses a drain cleaning composition containing causticalkali, a surface active wetting agent and potassium hypochlorite as anoxidizing agent. However, neither of these patents disclosescompositions containing red-ox mixtures in combination with causticalkali.

Several patents disclose compositions containing red-ox mixtures withsmall amounts of alkaline ingredients strictly for pH control. Examplesof these are U.S. Pat. Nos. 3,804,771 to Margolis; 3,341,418 to Moses etal; and 3,632,516 to Antonelli et al.

In contrast to the above mentioned prior art, Applicant has hereinunexpectedly found that improved drain cleaning performance can beobtained utilizing a drain cleaning composition containing causticalkali in combination with red-ox mixtures. Such compositions haveimproved solubility characteristics which tend to prevent the formationof caustic alkaline precipitates of unreacted ingredients in thedrainpipe being treated. Additionally, these formulations provideimproved clog-dissolving capabilities as well as hair attackcapabilities due to the improved heat generating properties of thecomposition.

SUMMARY OF THE INVENTION

A drain cleaning composition consisting essentially of:

(a) from about 20 to 60 weight percent of an oxidizing agent;

(b) from about 1 to 30 weight percent of a reducing agent; and

(c) from about 20 to 75 weight percent of an alkali metal hydroxide,wherein said composition produces upon dissolution in water at least 230calories of heat per gram of composition and sufficient turbulence tosubstantially prevent the formation of an insoluble caustic heel,wherein said oxidizing and reducing agents are physically separateduntil utilization in the presence of water.

Preferred oxidizing agents are alkali metal salts of a member selectedfrom the group consisting of perborate tetrahydrate, persulfate,carbonate peroxide, peroxide and mixtures thereof.

Preferred reducing agents are selected from the group consisting ofdextrose, thiourea, an alkali metal salt of thiosulfate and mixturesthereof.

A preferred composition is one consisting of the following ingredients:

thiourea pellets: 4.0 grams

sodium perborate tetrahydrate: 25.0 grams

sodium hydroxide: 30.0 grams

anhydrous sodium silicate: 1.0 gram

DETAILED DESCRIPTION OF THE INVENTION

The drain cleaning compositions in accordance with the invention containas essential ingredients a reducing agent, an oxidizing agent and analkali metal hydroxide. The ingredients, of course, may be either in theliquid or crystalline solid form. Preferably, to prevent interactionbetween the reducing agent and the oxidizing agent prior to use, theseingredients are kept physically separated until actual utilization fordrain cleaning purposes. Therefore, for example, the drain cleaningcomposition can be packaged in a compartmentalized container in whichthe reducing agent plus sodium hydroxide is maintained in onecompartment and the oxidizing agent is maintained in the othercompartment. In some instances, the oxidizing agent may be compatiblewith sodium hydroxide and, therefore, packaged together, whilemaintaining the reducing agent in a separate compartment. At the time ofactual utilization, the ingredients from each compartment are pouredsimultaneously into the clogged trap and, as they reach the water in thebottom of the trap, reaction begins creating enough heat to bring thetemperature of the water near boiling.

Since the drains for most kitchen and bathroom sinks often becomeclogged with a combination of fatty substances and protein fibers suchas hair, it is important that the drain cleaning compositions be able todissolve both of these types of clogging substances. To effectivelydissolve the fatty type of clogging material in a drain, it has beendetermined that the drain cleaning compositions disclosed herein, whichprovide at least 230 calories of heat per gram of composition dissolvedin water, are most effective in dissolving this type of cloggingmaterial. At values much below 230 calories per gram, there isinsufficient heat produced to perform an effective drain cleaningfunction. Furthermore, the drain cleaning compositions disclosed hereinwill generally have an excess of oxidizing agent which, in combinationwith hot alkaline solution, proves to be most effective in attacking anddissolving hair, thereby alleviating the other type of clogging problemnormally encountered. Finally, it has been observed that the presentcompositions provide for a controlled amount of turbulence duringreaction in the water in a drain trap due to the evolution of gaseousmaterials resulting from the reaction. These gases, which may forexample be oxygen or carbon dioxide, provide for a greater degree ofmixing of the ingredients in the drain trap, allowing movement of thedrain cleaning mixture to other portions of the piping further removedfrom the drain trap. This turbulence prevents the formation of aninsoluble precipitate of unreacted ingredients called a "caustic heel"which can, more often than not, create a worse clogging problem thanthat initially encountered before addition of the drain cleaningcomposition. Such caustic heel formations are frequently encounteredwhen drain cleaning compositions disclosed by the prior art are used.

Generally, between 20 and 75 weight percent of an alkali metal hydroxideis preferred in the compositions disclosed herein. At concentrationsbelow 20 percent, insufficient hair attack is observed; whereas, atconcentrations above 75 percent, no noticable improvement in theeffectiveness of the drain cleaning composition is observed. The term"alkali metal", which is used herein and throughout the remainingportion of this disclosure, is intended to have its normal acceptedmeaning in the art. However, because of commercial availability andrelatively lower cost, both sodium and potassium hydroxide are preferredfor use herein.

Many combinations of oxidizing and reducing agents can be utilized as isgenerally known in the art, provided they meet the required criteria foruse in drain cleaning compositions, as previously discussed. Forexample, the compositions must provide the required heat evolution upondissolution in water (i.e. at least 230 calories per gram), and also besoluble and provide turbulence effects to prevent the formation of aninsoluble caustic heel in the drain trap. Additionally, the proportionsof oxidizing to reducing agent can be balanced so that an excess of oneor the other would be available for reaction with the materials cloggingthe drain, and after the heat producing reaction has been completed.Thus, an excess of oxidizing agent has been observed to improve thecapability for hair attack by sodium hydroxide.

With respect to the oxidizing agent, it has been generally found that 20to 60 weight percent in the composition provides a sufficient amount ofthis ingredient to result in the required evolution of heat and a slightexcess of the oxidizing agent for hair attack, as described above.Although many known oxidizing agents can be used, those preferred arealkali metal salts of perborates, persulfates, carbonate-peroxides andperoxide such as sodium persulfate (Na₂ S₂ O₈), sodium perboratemonohydrate or tetrahydrate (NaBO₂. H₂ O₂. H₂ O or NaBO₂. H₂ O₂. 3H₂ O),sodium carbonate-peroxide (Na₂ CO₃. H₂ O₂. 1/2H₂ O) and sodium peroxide(Na₂ O₂). Others might be used, such as potassium permanganate (KMnO₄),potassium dichromate (K₂ Cr₂ O₇), lithium hypochlorite (Li O CL),potassium peroxymonosulfate (KHSO₅) or sodium dichloroisocyanurate (Cl₂Na (NCO)₃).

With regard to the reducing agents, generally from 1 to 30 weightpercent has been found to be sufficient to react with all or part of theoxidizing agent to provide the required heat generation. Preferredreducing agents are sodium thiosulfate (Na₂ S₂ O₃), reducing sugars (C₆H₁₂ O₆ etc.), and thiourea ([NH₂ ]₂ CS). Others may be used, such assodium bisulfite (NA HSO₃), sodium borohydride (NaBH₄), hydrazine saltsNH₂ NH₂. H₂ SO₄ etc.), sodium hypophosphite (NaH₂ PO₂. H₂ O).

The following red-ox mixtures having varying degrees of causticalkalinity are examples of those which could be used in accordance withthe invention:

    ______________________________________                                        Oxidizing Agent     Reducing Agent                                            ______________________________________                                        potassium peroxymonosulfate, KHSO.sub.5                                       sodium chloride NaCl                                                          lithium hypochlorite, LiOCl                                                   thiourea, (NH.sub.2).sub.2 CS                                                 K and Na dichloroisocyanurate,                                                thiourea, (NH.sub.2).sub.2 CS                                                  (Cl.sub.2 Na(NCO).sub.3)                                                     sodium peroxide, Na.sub.2 O.sub.2                                             thiourea, (NH.sub.2).sub.2 CS                                                 sodium peroxide, Na.sub.2 O.sub.2                                             sodium thiosulfate,                                                                                Na.sub.2 S.sub.2 O.sub.3                                 sodium peroxide, Na.sub.2 O.sub.2                                             sodium sulfite, Na.sub.2 SO.sub.3                                             sodium peroxide, Na.sub.2 O.sub.2                                             sodium bisulfite, NaHSO.sub.3                                                 sodium peroxide, Na.sub.2 O.sub.2                                             sodium phosphite,                                                                                  Na.sub.2 HPO.sub.3                                       sodium peroxide, Na.sub.2 O.sub.2                                             sodium hypophosphite,                                                                              NaH.sub.2 PO.sub.2                                       sodium peroxide, Na.sub.2 O.sub.2                                             sodium nitrite, NaNO.sub.2                                                    sodium peroxide, Na.sub.2 O.sub.2                                             sucrose or dextrose,                                                                               C.sub.6 H.sub.12 O.sub.6                                 sodium perborate monohydrate,                                                 sucrose or dextrose,                                                           NaBO.sub.2 . H.sub.2 O.sub.2 . H.sub.2 O                                                          C.sub.6 H.sub.12 O.sub.6                                 sodium perborate tetrahydrate,                                                sucrose or dextrose,                                                           NaBO.sub.2  . H.sub.2 O.sub.2 . 3H.sub.2 O                                                        C.sub.6 H.sub.12 O.sub.6                                 sodium carbonate-peroxide,                                                    sucrose or dextrose                                                            Na.sub.2 CO.sub.3 . H.sub.2 O.sub.2 . 1/2H.sub.2 O                                                C.sub.6 H.sub.12 O.sub.6                                 sodium carbonate-peroxide,                                                    sodium thiosulfate,                                                            Na.sub.2 CO.sub.3 . H.sub.2 O.sub.2 . 1/2H.sub.2 O                                                Na.sub.2 S.sub.2 O.sub.3                                 sodium carbonate-peroxide,                                                    thiourea, (NH.sub.2).sub.2 CS                                                  Na.sub.2 CO.sub.3 . H.sub.2 O.sub.2 . 1/2H.sub.2 O                           sodium carbonate-peroxide,                                                    lactose, C.sub.12 H.sub.22 O.sub.11                                            Na.sub.2 CO.sub.3 . H.sub.2 O.sub.2 . 1/2H.sub.2 O                           sodium carbonate-peroxide,                                                    urea, (NH.sub.2).sub.2 CO                                                      Na.sub.2 CO.sub.3 . H.sub.2 O.sub.2 . 1/2H.sub.2 O                           potassium peroxymonosulfate, KHSO.sub.5                                       thiourea, (NH.sub.2).sub.2 CS                                                 potassium peroxymonosulfate, KHSO.sub.5                                       sodium thiosulfate,                                                                                Na.sub.2 S.sub.2 O.sub.3                                 potassium persulfate, K.sub.2 S.sub.2 O.sub.8                                 sodium bisulfite, NaHSO.sub.3                                                 potassium persulfate, K.sub.2 S.sub.2 O.sub.8                                 dextrose, C.sub.6 H.sub.12 O.sub.6                                            sodium persulfate, Na.sub.2 S.sub.2 O.sub.8                                   Igepal DM 970 (GAF)                                                           sodium persulfate, Na.sub.2 S.sub.2 O.sub.8                                   Pluronic F 127 (BASF)                                                         sodium persulfate, Na.sub.2 S.sub.2 O.sub.8                                   Polawax (Croda)                                                               lithium hypochlorite, LiOCl                                                   ethylene glycol                                                                                    [(CH.sub.2).sub.2 (OH).sub.2 ]                           lithium hypochlorite, LiOCl                                                   glycerine,                                                                                        CHOH (CH.sub.2 OH).sub.2                                  periodic acid, HIO.sub.4                                                      ethylene glycol                                                                                   [(CH.sub.2).sub.2 (OH).sub.2 ]                            periodic acid, HIO.sub.4                                                      glycerine,                                                                                        CHOH (CH.sub.2 OH).sub.2                                  ______________________________________                                    

The following red-ox mixtures having varying degrees of causticalkalinity would be unsatisfactory for drain cleaner compositions inaccordance with this invention:

    ______________________________________                                        Oxidizer           Reducer                                                    ______________________________________                                        sodium perborate,                                                             sodium nitrite, NaNO.sub.2                                                    NaBO.sub.2 . H.sub.2 O.sub.2 . 3H.sub.2 O                                     sodium carbonate-peroxide,                                                    sodium nitrite, NaNO.sub.2                                                    potassium nitrate                                                             sodium thiosulfate                                                            ______________________________________                                    

Certainly these are not a complete list of all combinations that couldor could not be used in the drain cleaner. Any of the alkali metalscould be used in place of the ones specifically mentioned. Certainlyorganic oxidizing agents could be used, but are not preferred because ofgeneral instability problems at higher temperatures, and cost. Anyattempt at classifying the oxidizers and reducers that produce aneffective formulation is difficult. In general, it is necessary for thereactants to be soluble in water and caustic solutions. They should bestable at elevated temperatures. The redox reaction should produceenough turbulence to dissolve the formulation completely. This isusually accomplished by the release of gaseous oxygen from the oxidizerbut that is not to say it is the only way to produce a turbulentreaction. The oxidizer should be of a strong enough nature to react withthe reducing agent of choice without producing excessive turbulence or alarge volume of insoluble precipitate. Either the oxidizer or thereducer must be compatible with anhydrous alkali metal hydroxide inorder to package the product in a dual compartment pouch.

Additional optional ingredients such as perfumes, dyes, wetting agents,corrosion inhibitors, etc. can be added to the drain cleaningcompositions to provide preferred properties thereto. Wetting agentsthat are compatible with the ingredients in the composition can beincluded to increase the rate at which the drain opener penetrates thefatty substance which clogs the drain or, in other instances, to providefoaming properties to increase the degree of contact of the draincleaning composition with the clogging materials. Examples of suchwetting agents are sodium alpha olefin sulfonates (e.g. Ultra Wet AOK)and ethoxylated alcohols.

Corrosion inhibitors, such as alkali metal silicates may be added toprevent metal attack of the plumbing fixtures by the drain cleaningcomposition. Also, to provide a dry, free-flowing mixture with sodiumhydroxide, a desiccant (e.g. powdered alumina, powdered sodium silicateand magnesium sulfate) is added in small amounts. Generally, theconcentration for each type of optional additive is less than about 5weight percent.

In some cases, it has been found that the drain cleaning compositionsproduce an excessive amount of turbulence in the drain trap. To slowdown the degree of turbulence which is a direct result of theinteraction of the red-ox ingredients, it has been found desirable topelletize one or more of these ingredients. Thus, a highly preferreddrain cleaning composition, in accordance with the present invention, isone having the following composition:

thiourea pellets: 4.0 grams

sodium perborate tetrahydrate: 25.0 grams

sodium hydroxide: 30.0 grams

anhydrous sodium silicate: 1.0 gram

The pelletized thiourea was made by mixing 76.05 weight percentthiourea, 19.01 weight percent of Ultra Wet AOK and 4.94 weight percentof Sunflex 107 oil (the weight percentages being based on the 4 gramweight of thiourea pellets) and running this mixture through apelletizing mill to produce pellets having a size such that they passthrough an 8 U.S. sieve mesh and are retained on a 14 U.S. sieve mesh.The Sunflex 107 oil is a mineral oil having a viscosity of 68-75 SayboltUniversal Seconds at 100° F. Of course, other types of mineral oils canbe used in its place.

For purposes of the disclosure herein, it is understood that the conceptof oxidation-reduction (referred to as "red-ox") is that interactionwhich occurs between the two reagents when they are brought togetherunder proper conditions resulting in an exchange of electrons. Thereagent that is the electron donor is referred to as the reducing agentand the electron accepting reagent is the oxidizing agent.

In the examples that follow, it is to be understood that they are merelyillustrative of the present invention, and should not be deemed aslimiting the scope of the invention which is defined by the appendedclaims.

The test procedure and criteria used to evaluate the effectiveness ofthe drain cleaning compositions in accordance with the present inventionwas as follows:

(a) Solubility was determined by observation of a 50 to 60 gram chargeof the formula in a 11/4 inch glass drain trap containing 250 ml tapwater. If the formula was not completely dissolved within a 15 minuteperiod, or if there was evidence of formation of precipitates thecomposition was considered unsatisfactory.

(b) Turbulence during the process of solubilizing was considered anecessary parameter for the compositions tested. Turbulence greatlyincreases the rate of solubilization and helps to dislodge a clog from adrain. Controlled turbulence provides a means for pushing a quantity ofhot alkaline solution up out of the "U" bend of a drain trap and outinto the lateral line away from the trap in order to attack clogs thatmight occur in this lateral line. The degree of turbulence was observedfor each charge of material in the 11/4 inch glass trap containing 250ml tap water. Compositions providing excessive amounts of turbulence orno turbulence whatsoever were considered unsatisfactory.

(c) Heat production of a given formula was determined by dissolving a 50to 60 gram charge in 800 l ml deionized water in a calorimeter. Thetemperature rise in degrees centigrade (i.e. T) over a 30 minute periodwas noted on a centigrade thermometer and the calories of heat producedwere determined by the following equation.

    Calories/gm of charge=(T×800)/Charge (grams)

T=temp. rise in degrees centigrade

C=Total charge of material in grams

(d) Rate of hair attack was also determined. This was done by suspending1 gram of hair in 250 ml tap water in an 11/4 inch glass trap, addingthe formulation and determining how long it took for the hair tocompletely dissolve.

EXAMPLE 1

    ______________________________________                                        thiourea, (NH.sub.2).sub.2 CS                                                                        4g      7.4%                                           sodium perborate, tetrahydrate                                                 NaBO.sub.2 . H.sub.2 O.sub.2 . 3H.sub.2 O                                                          20g      37.1%                                          sodium hydroxide, NaOH                                                                              30g      55.5%                                          Total charge -        54g      100.0%                                         ______________________________________                                    

solubility in glass and metal traps was complete with no precipitateformation.

Turbulence tended to be more intense than was desirable, especially in ametal trap.

This formula was maximized for heat generation in a calorimeter and thearea between 4 and 6 grams thiourea produced maximum heat-- 268calories/gram.

1 gram hair was solubilized within 3 minutes.

EXAMPLE 2

    ______________________________________                                        thiourea, (NH.sub.2).sub.2 CS                                                                       1g      1.8%                                            sodium persulfate, Na.sub.2 S.sub.2 O.sub.8                                                        25g      44.6%                                           sodium hydroxide, NaOH                                                                             30g      53.6%                                           Total charge -       56g      100.0%                                          ______________________________________                                    

Solubility and turbulence were good in a glass trap. 13,200 calories ofheat were produced in calorimeter tests, or 236 cal/gram. The maximumheat production was obtained with 4 grams thiourea, 277 calories/gram,however, the rate of the reaction became undesirable at this level.

A one gram charge of hair was completely dissolved by this formula in 3minutes.

EXAMPLE 3

    ______________________________________                                        thiourea, (NH.sub.2).sub.2 CS                                                                        1.0g     1.7%                                          sodium thiosulfate, Na.sub.2 S.sub.2 O.sub.3                                                         1.0g     1.7%                                          sodium metasilicate anhydrous                                                  Na.sub.2 SiO.sub.3    1.0g     1.6%                                          Ultrawet AOK, alpha olefin sulfonate                                                                 0.75g    1.2%                                          sodium persulfate, Na.sub.2 S.sub.2 O.sub.8                                                          22.0g    36.2%                                         sodium hydroxide, NaOH 35.0g    57.6%                                         Total charge -         60.75g   100.0%                                        ______________________________________                                    

Sodium thiosulfate was employed in the above formulation to provide alittle more control of turbulence while increasing the amount of heatproduced.

The sodium metasilicate was used as a desiccant under storage conditionsand as a corrosion inhibitor for metal traps.

Alpha olefin sulfonate increased the foam production, thus increasingthe amount of solution that could be forced up out of a drain trap andinto the lateral line.

Solubility and turbulence were satisfactory in a glass trap but thelatter was somewhat greater in a metal trap.

Calorimeter studies showed a maximum of 16,160 calories of heatproduced, or 262 calories gram.

EXAMPLE 4

    ______________________________________                                        dextrose, C.sub.6 H.sub.12 O.sub.6                                                                18.0g     26.4%                                           sodium carbonate peroxide                                                      Na.sub.2 CO.sub.2 . 1/2H.sub.2 O                                                                 20.0g     29.4%                                           sodium hydroxide, NaOH                                                                            30.0g     44.2%                                           Total charge -      68.0g     100.0%                                          ______________________________________                                    

Solubility in glass trap containing 250 ml tap water was essentiallycomplete within 15 minutes.

Turbulence was good and one gram hair was completely dissolved within 3minutes.

The formula was optimized for heat production by varying the quantitiesof dextrose and carbonate-peroxide. Maximum heat of 279 calories/gramwas attained at 18 grams dextrose, 20 grams sodium carbonate-peroxide.

Attack on one gram hair essentially complete within 3 minutes.

EXAMPLE 5

    ______________________________________                                        sodium thiosulfate, Na.sub.2 S.sub.2 O.sub.3                                                           5.0g                                                 sodium peroxide, Na.sub.2 O.sub.2                                                                      10.0g                                                sodium hydroxide, NaOH   35.0g                                                Total charge -           50.0g                                                ______________________________________                                    

Solution rate was rapid with much turbulence.

One gram hair was dissolved in 2 minutes. Heat was optimized by varyingthe quantities of sodium thiosulfate between 2 and 8 grams.

The 2 gram addition gave a value of 253 cal./gram.

The 8 gram addition gave 255 cal/gram.

With the 5 gram addition the value was 264 cal/gram.

EXAMPLE 6

    ______________________________________                                        thiourea, (NH.sub.2).sub.2 CS                                                                          3.0g                                                 sodium peroxide, Na.sub.2 O.sub.2                                                                      10.0g                                                sodium hydroxide, NaOH   35.0g                                                Total charge -           48.0g                                                ______________________________________                                    

Complete solubility of reactants was achieved within 1 minute in a glasstrap containing 250 ml tap water.

Much turbulence was observed during reaction.

3, 5 and 8 gram samples of thiourea were incorporated into the formulaand run in calorimeter. 3 grams gave a heat value of 359 cal/gram, 5grams a value of 351 cal/gram and 8 grams gave 332 cal/gram.

1 gram hair was dissolved in 2 minutes.

All of the above formulations produced somewhat excessive turbulence inmetal traps. Evidently the brass of a metal trap catalyzes the reactionmaking it much more rapid that in a glass trap.

In an attempt to slow down the rate of reaction and therefore the degreeof turbulence, the particle size of one of the reactants was increased.

EXAMPLE 7

Pelletized thiourea containing 76.05 thiourea, 19.01% Ultrawet AOK(alpha olefin sulfonate) and 4.94% Sunflex 107 oil was made by mixingthe ingredients and running the resulting mixture through a pelletizingmill. The pellets produced which were of a size such that they passedthrough an 8 mesh U.S. sieve screen, but were retained on a 14 mesh U.S.sieve screen. These pellets were used in the following formula:

    ______________________________________                                        thiourea pellets, (NH.sub.2).sub.2 CS                                                               4.0g     6.7%                                           sodium perborate tetrahydrate                                                  NaBO.sub.2 . H.sub.2 O.sub.2 . 3H.sub.2 O                                                          25.0g    41.7%                                          sodium hydroxide, NaOH                                                                              30.0g    50.0%                                          sodium silicate anhydrous, Na.sub.2 SiO.sub.3                                                       1.0g     1.6%                                           Total charge -        60.0g    100.0%                                         ______________________________________                                    

In a glass trap containing 250 ml tap water a steady controlledturbulence could be maintained for about 2 minutes. The charge wascompletely dissolved within this 2 minute period. Similar results wereobtained in metal traps.

One gram of hair was completely dissolved within 2 minutes. Calorimetertests showed a total heat production of 15,600 calories, or 260calories/gram of charge.

Additionally, satisfactory drain cleaning compositions are those inExamples 8 and 9.

EXAMPLE 8

    ______________________________________                                        sodium thiosulfate, Na.sub.2 S.sub.2 O.sub.3                                                           11.8%                                                sodium perborate tetrahydrate                                                  NaBO.sub.2 . H.sub.2 O.sub.2 . 3H.sub.2 O                                                             44.1%                                                sodium hydroxide, NaOH   44.1%                                                                         100.0%                                               ______________________________________                                    

EXAMPLE 9

    ______________________________________                                        sodium thiosulfate, Na.sub.2 S.sub.2 O.sub.3                                                           1.8%                                                 sodium persulfate, Na.sub.2 S.sub.2 O.sub.8                                                            44.6%                                                sodium hydroxide, NaOH   53.6%                                                                         100.0%                                               ______________________________________                                    

The following drain cleaning compositions in Examples 10-12 wereunsatisfactory.

EXAMPLE 10

    ______________________________________                                        sodium thiosulfate, Na.sub.2 S.sub.2 O.sub.3                                                            6.4g                                                potassium dichromate, K.sub.2 Cr.sub.2 O.sub.7                                                          2.0g                                                sodium hydroxide, NaOH                                                        ______________________________________                                         30.0g                                                                        Total charge -            38.4g                                               ______________________________________                                    

No turbulence was produced and a hard heel was left in trap.

EXAMPLE 11

    ______________________________________                                        thiourea, (NH.sub.2).sub.2 CS                                                                           6.0g                                                potassium dichromate, K.sub.2 Cr.sub.2 O.sub.7                                                          2.0g                                                sodium hydroxide, NaOH    30.0g                                               Total charge -            38.0g                                               ______________________________________                                    

Very little turbulence and much undissolved material left in glass trap.

EXAMPLE 12

    ______________________________________                                        potassium nitrate, KNO.sub.3                                                                           20.0g                                                dextrose, C.sub.6 H.sub.12 O.sub.6                                                                     16.0g                                                sodium hydroxide, NaOH   30.0g                                                Total charge -           66.0g                                                ______________________________________                                    

In a glass trap maximum temperature reached 220° F., but absolutely noturbulence was observed, and the dextrose was carbonized into a hardheel in bottom of trap.

What is claimed is:
 1. A drain cleaning composition consisting of thefollowing ingredients:thiourea pellets: 4.0 grams sodium perboratetetrahydrate: 25.0 grams sodium hydroxide: 30.0 grams anhydrous sodiumsilicate: 1.0 gramswherein said thiourea pellets consist of a mixturecontaining 76.05 weight percent thiourea, 19.01 weight percent sodiumalpha olefin sulfonate and 4.94 weight percent of a mineral oil, andsaid pellets are of a size which are capable of passing through theopenings of an 8 mesh U.S. sieve screen but are retained by a 14 meshU.S. sieve screen.